One man has been injured after part of a train's roof flew off as it approached a station in Sydney's inner west on Monday.
The Waratah train was pulling into Burwood Station about 1.30pm when witnesses said the roof "exploded".
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Train roof explosion injures passenger
An investigation has been launched after part of a train roof exploded, debris injured one man while narrowly missing others at Burwood Station. Vision: Seven News
"I heard 'kaboom', like firecrackers. Like fireworks," one witness told Seven News.
Another said he heard an "almighty bang".
![Debris left on the platform at Burwood on Monday afternoon.](/web/20170321080847im_/http://www.smh.com.au/content/dam/images/g/v/2/d/o/f/image.related.articleLeadwide.620x349.gv2ddc.png/1490074185841.jpg)
"We just sort of looked stunned. We thought it was a gas explosion or something," the witness said.
Breaking: Emergency services at Burwood train station after a reported explosion/fire on train carriage roof. 1 person been treated for inj pic.twitter.com/KlT3NnuA1l
— Shannon Carr (@ShannonCarr_10) March 20, 2017
Part of the roof hatch flew onto the opposite platform, as smoke began to rise from the roof of the affected carriage. Fire crews were called, but the small smouldering blaze "self-extinguished" by the time they arrived.
Trains on the T1 line were delayed through the afternoon. The platform was closed as emergency services and Sydney Trains workers investigated.
![Platform 3 was closed as workers and emergency services responded.](/web/20170321080847im_/http://www.smh.com.au/content/dam/images/g/v/2/f/0/s/image.related.articleLeadwide.620x349.gv2ddc.png/1490074181292.jpg)
Sydney Trains chief executive Howard Collins said a man in his 50s was injured in the incident. The commuter suffered bruising but no serious injuries and was treated at the scene by paramedics.
"He had bruising to his chest. He was treated by the ambulance crew. There was no sign of any flesh wounds, just bruising," Mr Collins said.
![Transport minister Andrew Constance issued an apology to the man who was injured.](/web/20170321080847im_/http://www.smh.com.au/content/dam/images/g/v/2/f/0/u/image.related.articleLeadwide.620x349.gv2ddc.png/1490074181292.jpg)
"We had a flashover of the static inverter on top of the Waratah train. That caused debris to fall outside the train, and also some interior damage."
Mr Collins said he had never seen anything like it in four decades of working with trains.
![Sydney Trains chief executive Howard Collins said he had never seen anything like it.](/web/20170321080847im_/http://www.smh.com.au/content/dam/images/g/v/2/f/0/5/image.related.articleLeadwide.620x349.gv2ddc.png/1490074181292.jpg)
"Train services obviously were delayed while the police, quite rightly, evacuated the area [and] made sure it was safe," he said. "In my 40 years of working on the railways I've never seen the hatches of a train come off in this manner.
"This is a serious matter. It's got to be dealt with. We want to find out exactly what caused it - we want to ensure it's eliminated."
NSW Transport Minister Andrew Constance issued an apology to the injured man on Monday evening, as NSW Labor demanded an explanation for what happened.
"I'd like to offer my sincere apologies to the man injured after today's incident at Burwood train station," Mr Constance said in a statement.
"The Australian Transport Safety Bureau and Office of Transport Safety Investigations will both be conducting examinations of the train that has been damaged.
"Sydney Trains is also liaising with maintenance provider Downer to understand the history of the Waratah train involved and any actions that need to be taken as a matter of priority."
Shadow transport minister Jodi McKay said the government "certainly has questions to answer".
"Is this a fault with the train? Is this a maintenance issue? How on earth did this happen?" she asked.
"We're lucky no one was killed."
with AAP